JP3035429B2 - Speed change operation structure of walking type work machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed change operation structure in a walking type working machine such as a walking type cultivator and a walking type management machine.

[0002]

2. Description of the Related Art For example, Japanese Unexamined Patent Publication No.
As disclosed in Japanese Patent Application Publication No. 0231, a transmission unit is provided with a main transmission device capable of shifting to a plurality of forward stages and a reverse position, and a subtransmission device capable of shifting to a high speed side and a low speed side. The main transmission lever and the sub transmission lever are provided with a main transmission lever for operating the transmission and an auxiliary transmission lever for operating the transmission of the sub transmission, and the main transmission and the sub transmission are separately operated by the main transmission lever and the sub transmission lever. There are things.

[0003]

In the above-mentioned walking type working machine, when the shift operation of the main transmission and the auxiliary transmission is performed, the operator must change the main transmission lever and the auxiliary transmission lever. There is room for improvement in operability.
SUMMARY OF THE INVENTION It is an object of the present invention to improve the speed change operability in a speed change operation structure of a walk-behind work machine provided with a main transmission and a sub transmission in a transmission case.

[0004]

The feature of the present invention resides in the following structure in the speed change operation structure of a walking type working machine as described above. [1] A main transmission capable of shifting to a plurality of forward stages and a reverse stage;
The transmission case is provided with a subtransmission that can be shifted to a high-speed side and a low-speed side, and a shift lever that is swingable around a horizontal axis in the left-right direction and swingable around a vertical axis is provided.
The auxiliary transmission shaft is supported on the transmission case along the left and right direction, and a shift fork for shifting the operation of the auxiliary transmission is slidably fitted on the auxiliary transmission shaft to swing the transmission lever around the horizontal axis in the left and right direction. A first linking mechanism that transmits the dynamic operation to the sub-transmission shaft to rotate the sub-transmission shaft, and shifts the sub-transmission by sliding the shift fork along the sub-transmission shaft with the rotation of the sub-transmission shaft. A shift mechanism is operated to swing to one side around the horizontal axis in the left-right direction, and the sub-transmission is shifted to a lower speed side; When the sub transmission is shifted to the high speed side by swinging operation to the other range around the shaft center, the main transmission is shifted freely to a plurality of forward stages and to the reverse side by the transmission lever. Second link for linking the main transmission and It is equipped with a mechanism.

[2] A main transmission capable of shifting to a plurality of forward stages and a reverse stage;
The transmission case is provided with a subtransmission that can be shifted to a high-speed side and a low-speed side, and a shift lever that is swingable around a horizontal axis in the left-right direction and swingable around a vertical axis is provided.
The plurality of main transmission shafts of the main transmission and the auxiliary transmission shaft of the auxiliary transmission are projected outward from the side of the transmission case,
A first linkage mechanism for transmitting the swinging operation of the speed change lever about the horizontal axis in the left-right direction to the auxiliary speed change shaft and rotating the auxiliary speed change shaft, and along the auxiliary speed change shaft along with the rotation of the auxiliary speed change shaft. A cam mechanism for shifting the sub-transmission by sliding the shift fork, and the transmission lever is rocked to one side around the horizontal axis in the left-right direction to shift the sub-transmission to the lower speed side. In the left and right directions around the horizontal axis of the speed change lever in a state in which the speed change lever is swingingly operated to the other range around the horizontal axis in the left and right direction and the speed change operation is performed on the high speed side. One of the plurality of main transmission shafts is selected by the swing operation, and the selected main transmission shaft is slid by the swing operation around the longitudinal axis of the transmission lever, so that the main transmission is moved forward. The shift lever is operated so that the gear can be shifted to multiple speeds and to the reverse side. It is provided with a second linkage mechanism for linking the main transmission.

[0006]

According to the first aspect of the present invention, the main transmission is driven through the second linkage mechanism by swinging the shift lever about the horizontal axis and the vertical axis in the left-right direction. The speed is shifted to a plurality of speeds and to the reverse side, and by operating the speed change lever about the horizontal axis in the left-right direction, the speed of the sub-transmission is reduced through the first linkage mechanism, the auxiliary transmission shaft, and the shift fork. The shift operation is performed to the right side and the high speed side. Thus, the shift operation of both the main transmission and the auxiliary transmission can be performed by one shift lever.

[II] According to the feature of the first aspect, the state in which the shift lever is operated to swing in one range around the horizontal axis in the left-right direction and the sub-transmission is operated to shift to the low speed side, and The main transmission is operated by the main transmission lever to move the main transmission to a plurality of forward gears in both the state where the auxiliary transmission is operated to shift to the high speed side while the sub transmission is shifted to the high speed side around the horizontal axis in the left-right direction. The gear can be shifted to the reverse side.

[III] Many walking-type working machines have a transmission shaft of an auxiliary transmission arranged along the left-right direction of a transmission case. With this arrangement, the sub-transmission shaft is arranged along the left-right direction of the transmission case in the same manner as the transmission shaft of the sub-transmission, and when the shift fork for performing a shift operation is fixed to the sub-transmission shaft, the sub-transmission shaft is moved in the left-right direction of the transmission case. It is necessary to configure so as to slide along. When the sub-transmission shaft is configured as described above, when the transmission lever slightly away from the sub-transmission shaft and the sub-transmission shaft are mechanically linked, a transmission arm extended from the transmission lever is connected to the sub-transmission shaft. , The sub transmission shaft is slid. As a result, when an attempt is made to slide the sub-transmission shaft, a koji phenomenon may occur on the sub-transmission shaft, and a state may occur in which the sliding operation of the sub-transmission shaft cannot be performed properly.

According to the first aspect of the present invention, when the shift lever is swung about the horizontal axis in the left-right direction, the swinging operation of the shift lever about the horizontal axis in the left-right direction is performed by the first link mechanism. The transmission is transmitted to the shaft, the sub-transmission shaft is rotated, the shift fork is slid along the sub-transmission shaft by the action of the cam mechanism, and the sub-transmission is shifted. In the case of the speed change lever slightly away from the auxiliary speed change shaft, the speed change lever is used to rotate the auxiliary speed change shaft. The gear shifting operation of the device can be performed without any trouble.
In this case, since the swing operation of the speed change lever around the horizontal axis in the left-right direction and the auxiliary speed change shaft intersect with each other, the speed change lever and the auxiliary speed change shaft are configured by a link or the like. Just by linking with a relatively simple first linking mechanism,
The swing operation of the transmission lever around the horizontal axis in the left-right direction can be accurately transmitted to the auxiliary transmission shaft to rotate the auxiliary transmission shaft.

[IV] According to the feature of claim 2, similar to the case of claim 1, the "action" described in the above-mentioned [I], [II], and [III] is provided. It has various “actions”.
According to the feature of claim 2, the plurality of main transmission shafts of the main transmission and the auxiliary transmission shaft of the auxiliary transmission project outward from the side surface of the transmission case, and the transmission lever is moved around the horizontal axis in the left-right direction. When the swing operation is performed, one of the plurality of main transmission shafts is selected, and when the shift lever is operated to swing about the longitudinal axis, the selected main transmission shaft is slid, and the main transmission is moved forward. The shift operation is performed to a plurality of stages and the reverse side. By swinging the shift lever about the horizontal axis in the left-right direction, the sub-transmission is shifted to a lower speed or a higher speed via the first linkage mechanism, the auxiliary transmission shaft, and the shift fork.

In this case, in the swinging operation of the shift lever around the horizontal axis in the left-right direction, only one of the plurality of main shift shafts is selected, and the shift operation of the main transmission is not performed, and the vertical shift is performed. When the selected main transmission shaft is slid by the swing operation of the transmission lever around the center, the transmission operation of the main transmission is performed. Thus, the shifting operation of the shift lever, in which the shifting operation of the main transmission is not performed, is performed as in the swinging operation of the shift lever around the horizontal axis in the left-right direction. Thus, a state in which the speed change operation of the main speed change device and the speed change operation of the auxiliary speed change device are performed simultaneously does not occur. Therefore, the speed change operation of the main transmission and the speed change operation of the auxiliary transmission can be performed independently and accurately without affecting the speed change operation of the main transmission and the speed change operation of the auxiliary transmission. become.

[0012]

According to the first aspect of the present invention, in a speed change operation structure of a walking type work machine having a main case and a sub speed change device in a transmission case, a speed change operation of the main speed change device and a sub speed change by one speed change lever. The shifting operation of the device can be performed, and the shifting operability of the walking type working machine can be improved.

According to the first aspect of the present invention, the shift lever is operated to swing in one range around the horizontal axis in the left-right direction and the sub-transmission is shifted to the lower speed side, and the shift lever is shifted in the left-right direction. The main transmission lever moves the main transmission to a plurality of forward gears and the reverse gear in both the state where the sub transmission is operated to shift to the high speed side by swinging operation to the other range around the horizontal axis. Since the speed change operation can be performed, the number of shift steps can be increased on both the forward side and the reverse side, and the speed change operation on the reverse side can be performed in both the one and the other ranges, and the walking type The shift operability of the work machine was further improved.

According to the characteristic of the first aspect, the swing operation of the shift lever around the horizontal axis in the left-right direction enables the shift operation of the auxiliary transmission device to be accurately performed without occurrence of the koji phenomenon. The reliability and reliability of the speed change operation of the walking type working machine could be improved. Further, the first linkage mechanism between the shift lever and the sub-transmission shaft can be simply configured, which is advantageous in terms of simplifying the structure.

According to the feature of claim 2, the "effect of the invention" of the above-mentioned claim 1 is provided similarly to the case of the claim 1. In addition to the "effect of the invention", the following "invention" is provided. Of the effect. According to the feature of claim 2, as the swing operation of the shift lever around the horizontal axis in the left-right direction,
The shifting operation of the auxiliary transmission is performed by the swinging operation of the transmission lever in which the shifting operation of the main transmission is not performed, so that the shifting operation of the main transmission and the shifting operation of the auxiliary transmission affect each other. As a result, the operation can be performed independently and accurately, and the reliability and reliability of the speed change operation of the walking-type working machine can be further improved.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to a walking type cultivator. As shown in FIG. 1, an engine 3 is provided at a front portion of a transmission case 2 provided with wheels 1 for traveling, and a steering handle 4 is provided on an upper portion of the transmission case 2 so as to be able to change its direction around the longitudinal axis Y1 in the longitudinal direction of the aircraft. To provide a walking-type cultivator.

The walk-behind cultivator includes a main transmission (not shown) and an auxiliary transmission (not shown), and a main transmission (not shown) is provided on a side surface of the transmission case 2 as shown in FIG. ) Is provided with a forward shift shaft 5a and a reverse shift shaft 5b capable of shifting the gears to two levels of high and low, and a sub-transmission shaft 6 capable of shifting the auxiliary transmission (not shown) to two levels of high and low. It is configured to be able to shift to four forward speeds and four reverse speeds by the auxiliary transmission.

On the side surface of the transmission case 2, the shift shafts 5a, 5b for forward and backward movement and the auxiliary transmission shaft 6 are operated.
A shift lever 7 is provided. The shift lever 7 is
One of the forward and reverse shift shafts 5a, 5b is selected by a swing operation about the horizontal axis X1 in the left-right direction, and the selected forward and reverse is selected by the swing operation about the vertical axis Y2. The shift shafts 5a and 5b are slidably operated. By swinging the shift lever 7 about the horizontal axis X1 in the left-right direction, the auxiliary shift shaft 6
Is rotated, and the shift fork 6 a externally fitted to the auxiliary transmission shaft 6 is slid by the cam mechanism 9 provided between the auxiliary transmission shaft 6 and the shift fork 6 a with the rotation of the auxiliary transmission shaft 6. .

As shown in FIGS. 2 and 5, a pair of lever receivers 5b1 are provided above and below the reverse shift shaft 5b, and the lever receiver 5a1 of the forward shift shaft 5a is disposed between the pair of lever receivers 5b1. ing. As a result, as shown in FIGS. 2 and 3, the shift lever 7 is
The swing operation is performed in four steps around one.

When the speed change arm 7a is engaged with the lower lever receiver 5b1 as shown in FIG. 2, when the reverse shift shaft 5b is selected by the speed change arm 7a, the sub speed change device is in the low speed position. Then, the main transmission is shifted on the reverse side (see the positions of R1 and R2 in FIGS. 2 and 4).
Next, when the speed change arm 7a is engaged with the lower portion of the lever receiver 5a1, when the forward shift shaft 5a is selected by the speed change arm 7a, the main speed change device is moved to the forward side while the auxiliary speed change device is at the low speed position. (See positions F1 and F2 in FIGS. 2 and 4).

As shown in FIGS. 2 and 3, the speed change arm 7a
Is engaged with the upper portion of the lever receiver 5a1, and when the forward shift shaft 5a is selected by the speed change arm 7a, the auxiliary speed change shaft 6 is moved through the link mechanism 8 and the cam mechanism 9.
The shift fork 6a, which is fitted on the outside, is slid from the low-speed position to the high-speed position. As a result, the main transmission is shifted on the forward side while the auxiliary transmission is in the high-speed position (see positions F3 and F4 in FIGS. 2 and 4). Next, when the shift arm 7a is engaged with the upper lever receiver 5b1,
When the reverse shift shaft 5b is selected by the transmission arm 7a, the main transmission is shifted on the reverse side while the auxiliary transmission is in the high-speed position (R3 in FIGS. 2 and 4).
R4 position).

As shown in FIG. 6, the cam mechanism 9 comprises a pin 9a protruding from the auxiliary transmission shaft 6, and an inclined cam groove 9b formed on the inner surface of the boss of the shift fork 6a. The shift fork 6a slides in the axial direction against the urging force of the ball detent mechanism 10 with the rotation of the speed change shaft 6 around the axis.

As shown in FIGS.
The guide plate 11 is provided with a gauge 12 that indicates the shift operation position of the shift lever 7 in conjunction with the shift lever 7.
The gauge 12 is provided on the side wall of the transmission case 2 with the spherical joint 1.
The horizontal axis X2 of the arm portion 7b rotatably supported through the base 2a and extending upward from the base end of the shifting arm 7a
A stay 13 is swingably supported around the periphery, and an upper portion of the gauge 12 passes through the stay 13. Thereby, it is swingable in the front-rear direction with the swinging operation of the shift lever 7 around the horizontal axis X1 in the left-right direction, and in the left-right direction with the swinging operation of the shift lever 7 around the vertical axis Y2. The gauge 12 is configured to be tiltable.

[Alternative Embodiment] In the above-described embodiment, a walk-type cultivator having four forward speeds and four reverse speeds has been described. However, the number of shift speeds such as six forward speeds and two reverse speeds can be changed.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is an overall side view of a walking tiller.

FIG. 2 is a side view of the vicinity of a shift lever and a link mechanism.

FIG. 3 is a side view showing a state in which a shift lever is operated upward from the state shown in FIG. 2;

FIG. 4 is a plan view near a guide plate and a gauge.

FIG. 5 is a plan view showing the vicinity of a forward and reverse shift shaft.

FIG. 6 is a plan view showing the vicinity of a cam mechanism of a subtransmission shaft.

[Explanation of symbols]

 2 Transmission case 5a, 5b Main transmission shaft 5a1, 5b1 Second linkage mechanism 6 Sub transmission shaft 6a Shift fork 7 Shift lever 8 First linkage mechanism 9 Cam mechanism X1 Horizontal axis in left and right direction Y2 Vertical axis

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60K 20/02

Claims (2)

(57) [Claims] 1. A plurality of stages on the forward side and a variable speed on the reverse side.
Main transmission and auxiliary transmission that can be shifted to high and low speeds
And a transmission lever (7) that is swingable around a horizontal axis (X1) in the left-right direction and swingable around a vertical axis (Y2).
In addition, the auxiliary transmission shaft (6) is supported on the transmission case (2) along the left-right direction, and a shift fork (6a) for shifting the operation of the auxiliary transmission is slidably moved on the auxiliary transmission shaft (6). fitted to, to transmit the rocking operation of the shift lever (7) of the horizontal axis (X1) around said lateral direction said to sub transmission shaft (6), the rotation operating the sub transmission shaft (6) The first linkage mechanism (8)
When the with the rotation of the sub transmission shaft (6), said sub transmission shaft (6)
The shift fork (6a) along with the sliding operation, a cam mechanism for shifting operation of the auxiliary speed change device and (9)
The shift lever (7) is provided with the horizontal axis (X1) in the left-right direction.
The auxiliary transmission is driven to swing in one range around the
A state in which the shift operation is performed to the high speed side, and the shift lever (7)
Swings around the horizontal axis (X1) in the other direction in the other range.
The auxiliary transmission was shifted to a higher speed side
In the state, the main transmission is operated by the transmission lever (7).
The gears can be freely shifted to a plurality of forward gears and a reverse gear.
Second linking mechanism for linking lever (7) and main transmission
(5a1) The speed change operation structure of the walking type working machine provided with (5b1) . 2. The speed changeable to a plurality of stages on the forward side and to the reverse side.
Main transmission and auxiliary transmission that can be shifted to high and low speeds
The transmission case is provided in the transmission case (2) , the swing operation is freely performed around the horizontal axis (X1) in the horizontal direction, and the vertical axis is
Equipped with a shift lever (7) that can swing freely around the core (Y2)
Then, the plurality of main transmission shafts (5a) and (5b) of the main transmission and the auxiliary transmission shaft (6) of the auxiliary transmission are projected outward from the side surface of the transmission case (2), A first linking mechanism (8 ) that transmits a swing operation of the speed change lever (7) about the horizontal axis (X1) to the auxiliary speed change shaft (6) to rotate the auxiliary speed change shaft (6). )
When the with the rotation of the sub transmission shaft (6), said sub transmission shaft (6)
The shift fork (6a) along with the sliding operation, a cam mechanism for shifting operation of the auxiliary speed change device and (9)
The shift lever (7) is provided with the horizontal axis (X1) in the left-right direction.
The auxiliary transmission is driven to swing in one range around the
A state in which the shift operation is performed to the high speed side, and the shift lever (7)
Swings around the horizontal axis (X1) in the other direction in the other range.
The auxiliary transmission was shifted to a higher speed side
In the state, the horizontal axis of the shift lever (7) in the left-right direction
(X1) The plurality of main transmission shafts are rotated by a swing operation around the main transmission shaft.
One of (5a) and (5b) is selected, and
The swing operation of the lever (7) around the longitudinal axis (Y2) is performed.
And the selected main transmission shafts (5a) and (5b) slide.
When operated, the main transmission shifts to a plurality of forward gears and a reverse gear.
Gear shift lever (7) and the main
Second linkage mechanisms (5a1) and (5b) for linking with the transmission.
A shifting operation structure of a walking type working machine provided with 1) .